Abstract
<jats:p> Photocatalytic pavement — road and airfield surfaces incorporating titanium dioxide (TiO <jats:sub>2</jats:sub> ) — targets the diffuse, use-phase, mobile-source emissions that constitute the majority of transportation’s greenhouse-gas footprint. We report independent laboratory and field results for the first commercially scalable retrofit photocatalytic system, which integrates photo-reactive TiO <jats:sub>2</jats:sub> into established pavement-preservation carriers (PlusTi™). Under ambient ultraviolet excitation, TiO <jats:sub>2</jats:sub> drives a non-selective redox cascade — an “artificial photosynthesis” — that mineralizes vehicle-borne CO <jats:sub>2</jats:sub> to durable bicarbonate and oxidizes NO <jats:sub>x</jats:sub> , VOCs, and tire/brake-wear microplastics. Verified performance includes a 41–61% reduction in CO <jats:sub>2</jats:sub> concentration at fieldspecification dose (>1,000 t CO <jats:sub>2</jats:sub> removed per lane-mile per year), ~60% NO <jats:sub>x</jats:sub> reduction, 94.8–99.6% microplastic particle-size reduction, and measurable urban-heat-island mitigation. We frame the treated road network as an ecosystem technology (ecotech): a distributed atmospheric-processing surface that performs ecosystem services at urban scale using only ambient solar energy, no machinery, and no land displacement. A companion contribution is methodological — an expansion of lifecycle carbon-accounting boundaries beyond the industry’s cradle-to-gate (A1–A3) convention to a cradle-to-grave framework with a use-phase (Scope 3, Category 11) removal module, supported by published ISO-compliant EPDs and a Measurement, Reporting and Verification (MRV) protocol now in peer review. </jats:p>